Exit trays and apparatus for collecting variously sized copy paper are generally well known. For example, see IBM Technical Disclosure bulletin Vol. 18, December 1975, pages 2059-60 and Vol. 20, No. 6, November 1977, pages 2122-24. These disclosures describe a sheet collecting system with a copier, comprising a sheet collecting tray formed by a base and an abutment ledge adjoining a side of the baseplate remote from the copier. Long copies are fed directly into the collecting tray by a first pair of conveyor rollers disposed a considerable distance in front of the abutment, and short copies, after passing the first pair of conveyor rollers, are deflected, by a sheet deflector which can be actuated selectively, to a second pair of conveyor rollers situated nearer the abutment. The second pair of conveyor rollers feed the short copies into the collecting tray.
This known apparatus is suitable for feeding sheets of different lengths to an abutment in a collecting tray. However, two pairs of conveyor rollers are required for this purpose, and a sheet deflector which has to be set to a specific position for processing short sheets in order to guide these short sheets via the second pair of rollers into the collecting tray. The result is a collecting system which is complex and occupies considerable space.
Another type of collection system is shown in Japanese Application No. JP-A 58-68734. In this application a tray having two parts and a conveyor system for feeding long and short sheets into the tray which conveyor system is located near an edge of the tray. However, because of the arrangement of the conveyor system, long and short sheets can not be delivered interchangeable, for example, a long sheet overlying both parts would interfere with a short sheet lying in just one of the parts.
It is, therefore, an object of the present invention to provide a sheet processing apparatus which has a simple sheet collecting system which is capable of collecting sheets of different lengths interchangeably.